“Killing them Safely” may look like an activist doc, but it doesn’t feel like it until a good 10 minutes in. Till then it may actually seem like a celebration of its pet target, the humble Taser. Told entirely with archival footage and the occasional interview, it shows three of the main figureheads of Taser International — brothers Rick and Tom Smith, the latter since resigned, and Steve Tuttle — crowing about how their non-lethal weapon may change the world. They were small-time business owners who struggled for years before finding their product adopted by police forces the world wide. An Arizona cop talks to the filmmakers about how Tasers helps cut down on accidental shootings and police brutality. It is, as Tuttle points out, the American Dream.

Then come the cracks in the dome. Police go from trigger-happy to Taser-happy. Victims of incapacitating electrical shocks include a six-year-old in his elementary school class and an 88-year-old grandmother. Then there’s Robert Dziekanski, a Polish man whose erratic behavior in a Vancouver airport in 2007 led to him being tasered three times, causing his death. In all cases Taser International has denied culpability and all lawsuits against them have been dismissed, even as those against police and local governments have, in many cases, not.

Berardini unearths a lot of damning evidence, including extensive medical tests done by the company that failed to catch how Tasers can, in certain cases, affect the heart. But it’s not a simple takedown of a ubiquitous product, which is good because if it was its argument can sometimes be flawed too. Some of the evidence is anecdotal, and the filmmakers only talk to a few individuals, not a bigger swath. Still, it’s clear it’s not a case of a few bad apples — a few cops who didn’t get sufficient training or were unable to control their emotions, like any stressed-out/hot-headed cop pushed too far.

And yet “Killing them Safely” is after something bigger — a larger condemnation of society and humanity. The heads of Taser International, who make and distribute every single Taser on the planet, have, like a lot of businesses and government agencies, created an elaborate bureaucracy that shields those at the top from responsibility. Among Berardini’s biggest gets is a series of depositions with the Smiths and Tuttle in which they testily answer tough charges of malpractice. They’re defensive and, at times, snappy, trying to worm their way out of accusations, against evidence, that they ignored key findings that came to light well after their global empire was in place.

Berardini, and his editor Robert Greene, don’t just structure their film around talking heads and graphs, and Berardini doesn’t do the usual activist doc deal of inserting himself into the footage or dominating the narration with stories about what made him interested in the subject and what he found. He’s never seen and heard once, briefly, at the end. Instead he turns to reams of footage that plays out, often close to its entirety. There’s scores of cellphone video of tasing-gone-bad out there. But the most fascinating is the deposition footage, which sometimes plays out for minutes at a time — eons, even in documentary filmmaking. We get to see their body language, see their faces that barely conceal contempt at being asked questions they should, if they were doing things right, be a breeze to answer. A highlight is Rick’s tetchy debate with his interrogators over whether he can take a bathroom break mid-grilling. (They deny him.)

Seeing the face of people trying to worm their way out of responsibility, even improving their product in light of new findings, makes this more than a doc that’s just asking questions, even if does undermine a business that has done its best to control its own narrative. We get to see the flawed humanity in people who add to a greater discomfort, perhaps without even realizing it. Instead of a simple takedown, “Killing them Safely” becomes a dark comedy about humanity’s knack for quickie solutions and our ability to lie to ourselves, especially when our noble deeds go awry.